This invention relates generally to a circuit protection device and, more particularly, to a system for providing Arc Fault Circuit Interrupter (AFCI) protection for multiple circuits.
Arc Fault Circuit Interrupter (AFCI) devices are commonly used to detect arcs in an electrical circuit, and to cut off the supply of power in a circuit when an arc is detected. Increasingly, electrical codes are requiring AFCI devices for bedrooms and other circuits where arc faults more frequently occur. An arc fault can result in a fire, and therefore there is a strong desire by homeowners, landlords, and the like to provide preventive devices, such as AFCI breakers.
In a conventional power distribution system, multiple AFCI breakers provide arc fault protection for the branch circuits of a load center. For example, primary power, typically from a utility, is fed to the load center, which has a main breaker that controls the supply of power from the primary power supply to a series of branch circuits. The branch circuits may include arc and ground fault protected circuits, ground fault only protected circuits, and other non-fault interrupted circuits. In a typical household application, the arc and ground fault protected circuits route power to bedroom outlets, the ground fault protected circuits route power to bathroom outlets, kitchen outlets, and outdoor outlets, and the other circuits route power to the remaining outlets, e.g., family rooms, hallways, living rooms, and the like.
Thus, in addition to the main breaker, the load center houses dedicated circuit breakers for each of the branch circuits. AFCI/GFCI breakers are used to provide arc and ground fault protection for the arc and ground fault protected circuits, GFCI breakers are used to provide ground fault protection for the ground fault protected circuits, and conventional current interrupting (CI) breakers are used to provide current overload/short circuit protection for the remaining circuits. The AFCI/GFCI breakers and GFCI breakers also provide current overload/short circuit protection in addition to arc and ground fault protection. In such a conventional implementation, a dedicated AFCI/GFCI breaker is needed for each of the arc and ground fault protected circuits. Thus, for a three bedroom home with two circuits per room, a total of six separate AFCI/GFCI breakers are needed at considerable more cost than GFCI-only or CI-only breakers. Moreover, if arc fault protection is desired for each of the circuits of a home, which will typically include twenty or more circuits, the cost increase is further amplified.
Despite the advantages of arc fault protection provided by AFCI breakers, the use of AFCI breakers has been limited as their cost is significantly more than conventional circuit breakers. The cost is amplified when considering that multiple AFCI breakers are needed to provide complete AFCI protection.